1. Field of the Invention
The present invention relates to a service provided via a network interfacing wireless public and private networks and, more particularly, to providing an Evolution Data Only (EV-DO) service in a network interfacing a wireless public network and a wired/wireless private network, in which the EV-DO service is provided via the private network.
2. Description of the Related Art
As a solution for providing voice communication and data services under an in-building office environment free of charges, a system grafting CDMA-RF technology on a local wired/wireless private branch exchange has appeared for the first time.
The present invention will be described herein with reference to the in-building wireless environment, wherein the in-building wireless environment refers to not only an office environment such as an office building but also a communication environment within a certain zone (e.g., a campus, an army camp, etc.).
A system where a wireless public network is interfaced with a wired/wireless private network makes it possible to make a call anywhere within the building, supports a hand-off function with the public wireless network upon exiting a local zone, and provides a variety of additional services, for example, forwarding an emergency message using a short message service, retrieving necessary in-building information at an external location if an intra-net is established, and so on.
However, this system does not currently support a local EV-DO service function via the private network.
This is because a terminal cannot determine whether the data received currently in the private network has been transmitted via the public network or the private network when the terminal transmits a signal requesting the local EV-DO service.
That is, if a local wireless terminal attempts a call to get a local private network EV-DO service in the network interfacing the wireless public network and the wired/wireless private network, the EV-DO service is provided via the public network unconditionally because there is no information indicating which of the public and private networks is providing the EV-DO service.
Consequently, there is a problem in that the EV-DO service via the private network is unavailable via the existing network where the wireless public network is interfaced with the wired/wireless private network.